Self-winding timepiece mechanism



March 30, 1954 o. SCHMITZ SELF-WINDING TIMEPIECE MECHANISM Filed May 9, 1951 Patented Mar. 30, 1954 UNITED STATES PATENT GFFICE Claims priority, application Switzerland May 10, 1950 2 Claims.

The present invention relates to a timepiece mechanism with a self-winding means comprising a mass oscillating about an axis having a gear-Wheel attached to the mass concentrically of the axis thereof, which gear-wheel meshes with a displaceable gear-wheel, which latter is arranged between two intermeshing transfer Wheels and, depending upon the swing of the swinging mass, meshes alternately with one or other of the transfer wheels and turnsit in the same direction, Whilst a pawl prevents the transfer wheels from turning backwards.

The annexed drawing shows two embodiments by way of example of a timepiece mechanism for pocket watches or wristlet watches.

Fig. 1 is a plan view of the timepiece mechanism according to one embodiment,

Fig. 2 is a section on the line 2-2 of Fig. 1.

The oscillating mass I swings about the axis I a and is rigidly attached to the boss 2a of the gear-wheel 2, the boss being rotatably mounted in the bridgepiece 2b. The gear-wheel 2 meshes with a small gear-wheel or intermediate gear 3 which is provided with a circular bore 3a in which an oval pin or supporting member 4 engages, so that the gear-wheel 3 can take up two different positions. Two rotatable and inter-meshing transfer wheels 5 and 5 are arranged in front of the gear-wheel 3, so that the pitch circle of the transfer wheel 6 touches the pitch circle of the gear-wheel 3 when the latter is in one position and the pitch circle of the transfer wheel 5 touches the pitch circle of the gear-wheel 3 when the latter is in the opposite position. If the mass moves clockwise, the gear wheel 2 rolls the small wheel 3 towards the transfer wheel 6 and causes it to mesh therewith, until it is restrained by the oval pin 4 of the bore 3a and turns the transfer wheel in the direction of the arrow 8. If the mass swings counter-clockwise the little wheel 3 is brought into mesh with the transfer wheel 5 until it is restrained by the bore 3a and the pin 4 and turns the transfer wheel 5 in the direction of the arrow 9. The direction of rotation of the transfer wheels is the same. A stop pawl 1 prevents the transfer wheels 5, 6 from turning backwards. One of the transfer wheels is coupled through an intermediate wheel, not shown, with the trunnion of the spring housing, not shown, and winds up the spring.

By reason of the generally oval cross-sectional shape .of the pin 4, the gear-wheel 3 is readily movable from engagement with one to the other of the transfer Wheels 5 and E. As may be seen from Figure 1, as the gear-wheel 3 is moved from one to the other of the transfer Wheels 5 and 6, by reason of the shorter length of the major axis 0f the Din 4 3S Compared with the diameter of the bore 3a of the gear-wheel 3. lateral movement is 2 possible of the gear-wheel 3 with respect to a line between the center of the axis of the gear-wheel 2 and the center of the oval pin d, thereby facilitating the change-over of the gear-wheel 3 from one transfer Wheel to the other.

What I claim is:

1. In a timepiece mechanism, a disengageable transmission gearing for converting oscillatory motion to intermittent unidirectional motion comprising a gear wheel providing oscillatory motion, a pair of intermeshing transfer wheels, an intermediate gear having a bore and driven by the gear wheel and alternatively engaged with one or the other of the transfer wheels, and a supporting member of generally oval cross-sectional shape engaging in the bore of the intermediate gear permitting lateral movement of the intermediate gear with respect to a line between the center of the axis of the gear wheel and the center of the supporting member, whereby upon an oscillatory movement of the gear wheel the intermediate gear moves laterally from one to the other of the transfer wheels for the rotation thereof so that the transfer wheels rotate with an intermittent unidirectional motion.

2. In a timepiece mechanism, a disengageable transmission gearing for converting oscillatory motion to intermittent unidirectional motion comprising a gear Wheel providing oscillatory motion, a pair of intermeshing transfer wheels, an intermediate gear having a bore and driven by the gear wheel and alternatively engaged with one or the other of the transfer wheels, and a supporting member of generally oval cross-sectional shape engaging in the bore of the intermediate gear permitting lateral movement of the intermediate gear with respect to a line between the center of the axis of the gear wheel and the center of the supporting member, the bore of the intermediate gear being of circular shape and having a diameter slightly larger than the major axis of the cross section of the supporting member, whereby upon an oscillatory movement of the gear wheel the intermediate gear moves laterally from one to the other of the transfer wheels for the rotation thereof so that the transfer wheels rotate with an intermittent unidirectional motion.

OTTO SCHMITZ.

References Cited in the file of this patent UNITED STATES PATENTS Lee May 8, 1951 

